In recent years, LEDs (light-emitting diodes) having a high output and high light-emitting efficiency are now in widespread use, and development of luminaire using the LEDs as light sources regardless of whether the lamp is for indoor or outdoor is in progress. The luminaire using the LEDs has a long service life and consumes leas power in comparison with existing luminaire such as fluorescent lamps. Therefore, running cost is low and the number of times of replacement of equipment or maintenance on the basis of service life can foe reduced.
For example, a straight tube lamp using LEDs arranged in a row as light sources, which can be used by being replaced instead of existing straight tube fluorescent lamp is in widespread use.